Preparation of Hybrid Alkaline Cement Based on Natural Zeolite As Sustainable Building Material

Alkaline hybrid type cement is an interesting multi-component system that incorporates a high content of mineral additions, low content of Portland clinker (CK) (< 40%), and alkaline activator. The development of these types of cement allows a significant reduction in the clinker factor, thus leading to an economic and mainly environmental benefit.This study explores the possible development of such cement. Hybrid cement samples were prepared by alkaline activation of the natural zeolite, mainly composed of mordenite, and utilizing a NaOH solution. After mixing with OPC and with an alkaline solution, zeolite-rich tuff formed cement pastes with an activator/binder ratio of 0.5 that were cured for 24 hours at room temperature and then for 7 days underwater. The optimal alternative was evaluated based on compressive strength, quantitative X-ray diffraction, and Fourier Transform Infrared spectroscopy. As a result, the best dosage was that of 60% zeolite ruch tuffs and 40% CEM Type I showing values of compressive strength of 10 and 14 MPa at 7 and 28 days, respectively.